Environment-friendly building material regenerated by using organic waste and preparation method thereof

Abstract

The application discloses an environment-friendly building material regenerated by using organic waste and a preparation method, and belongs to the field of building materials.The environment-friendly building material regenerated by using organic waste provided by the application comprises graphene-VAE coated fibers and micro-bubble cement paste with a mass ratio of 1:5-9.The graphene-VAE coated fibers are first dispersed into the micro-bubble cement paste, and are uniformly mixed to obtain fiber-micro-bubble cement paste; then the fiber-micro-bubble cement paste is poured and vibrated to be compacted to obtain a pouring body; finally, when the pouring body is initially cured, modified mortar is scraped and coated on the surface of the pouring body, and the environment-friendly building material regenerated by using organic waste is obtained after hardening.The environment-friendly building material has excellent mechanical properties and sound insulation effect, and can realize lightweight of the base material and prolong the service life of the building material.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of building materials, and particularly relates to an environmentally-friendly building material regenerated from organic waste and a preparation method thereof. BACKGROUND

[0002] With the increasing attention to environmental protection and sustainable development worldwide, the environmentally-friendly building material regenerated from organic waste has become an important development direction for the construction industry. This kind of building material is made of organic waste as raw material through professional process, which not only reduces the pollution of waste to the environment, but also provides new materials for the construction industry.

[0003] Traditional organic waste regeneration building materials are often heavy due to the limitation of raw materials and manufacturing process, which not only increases the transportation and construction cost, but also limits its application scenarios to some extent. Some organic waste regeneration building materials have the problem of dropping slag due to insufficient treatment of raw materials or unreasonable formula design, which reduces the service life and safety of the building materials. In terms of sound insulation performance, organic waste regeneration building materials also have some defects. Due to the limitation of raw materials and structure, the sound insulation effect of some regeneration building materials is not ideal, which cannot meet the requirements of modern buildings on sound insulation performance. SUMMARY

[0004] Based on the deficiencies of the prior art, the purpose of the present application is to provide an environmentally-friendly building material regenerated from organic waste and a preparation method thereof.

[0005] The first aspect of the present application is to provide an environmentally-friendly building material regenerated from organic waste, which comprises graphene-VAE coated fibers and micro-bubble cement paste with a mass ratio of 1:5-9.

[0006] The graphene-VAE coated fibers are prepared by the following steps:

[0007] (1) The organic waste is cut and soaked and pulped to obtain a fiber slurry;

[0008] (2) The graphene oxide is dispersed in deionized water to obtain a graphene oxide dispersion;

[0009] (3) The fiber slurry is mixed into the graphene dispersion liquid, and a reducing agent and a catalyst are added to reduce the graphene oxide, and the fiber residue is filtered;

[0010] (4) The fiber residue is frozen and dried to obtain graphene coated fibers;

[0011] (5) The graphene coated fibers are placed in a VAE (vinyl acetate-ethylene copolymer) emulsion, and a silane coupling agent is added dropwise, and then dried to obtain graphene-VAE coated fibers.

[0012] It should be noted that the hydroxyl groups on the cellulose and the oxygen-containing groups on the graphene oxide GO sheet can be physically adsorbed through hydrogen bonding and Van der Waals force, and GO can be partially reduced and self-assembled under catalysis, and the sheet layers are oriented and stacked on the fiber surface, and under the condition of freeze-drying, the graphene sheet layers are extended along the fiber axis to form a three-dimensional through-porous network, and the graphene network is coated on the fiber surface in a nanoscale, thereby improving the tensile strength of the fiber. 2+ The graphene network is coated on the fiber surface in a nanoscale, thereby improving the tensile strength of the fiber, and in addition, the silane coupling agent is used to cooperate with the VAE film forming, and the VAE emulsion forms an amphiphilic buffer layer on the fiber surface, the hydrophilic end of the vinyl acetate segment is more easily anchored to the cement product, and the hydrophobic end of the vinyl segment is more easily coated on the fiber to form an elastic protective film, which can buffer stress and reduce the occurrence of slag, thereby finally enhancing the mechanical strength and sound insulation performance.

[0013] In some embodiments, the organic waste is selected from at least one of waste paper, bamboo shell, bamboo fiber, and corn cob; and the mass ratio of the organic waste to the graphene oxide is 18-20:1.

[0014] In some embodiments, the reducing agent is selected from at least one of ascorbic acid and L-cysteine, and the amount of the reducing agent is 50-60% of the amount of the graphene oxide; the catalyst is selected from at least one of ferrous chloride, ferric chloride, and ferric ammonium citrate, and the amount of the catalyst is 20-30% of the amount of the graphene oxide.

[0015] In some embodiments, in step (4), the freezing is freezing in liquid nitrogen at -196℃ for 10-15 s, the drying temperature is -80 to -60℃, and the drying time is 2-3 h; the silane coupling agent is selected from at least one of KH-550, KH-560, and KH-570, and the amount of the silane coupling agent is 2-3% of the amount of the organic waste.

[0016] In some embodiments, the micro-bubble cement paste comprises, by weight fraction, cement 90-110 parts, nano-silica fume 6-8 parts, water reducing agent 0.6-0.8 parts, and protein foaming agent 0.2-0.4 parts.

[0017] In some embodiments, the micro-bubble cement paste is prepared by the following steps:

[0018] Step one: mixing the cement, nano-silica fume, water reducing agent, and water to be cluster-free to obtain a base paste;

[0019] Step two: foaming the protein foaming agent in water to generate wet foam;

[0020] Step three: adding the wet foam to the base paste to obtain the micro-bubble cement paste.

[0021] In some embodiments, the cement is selected from at least one of Portland cement, sulphoaluminate cement; the amount of water in step one is 35-40% of the total amount of cement and nano-silica; and the mass ratio of the protein foaming agent to water in step two is 1:38-42.

[0022] It should be noted that the nano-silica in the micro-bubble cement paste is used to fill the gaps between the cement particles to improve the density, the protein foaming agent is used to stabilize the bubble shape and enhance the elasticity, and the water reducing agent is inserted between the protein molecules to inhibit the fusion and annexation of the bubbles.

[0023] The second aspect of the present application provides a preparation method of an environmentally-friendly building material regenerated from organic waste, comprising the following steps:

[0024] S1: dispersing the graphene-VAE coated fiber into the micro-bubble cement paste to obtain a fiber-micro-bubble cement paste;

[0025] S2: pouring and vibrating the fiber-micro-bubble cement paste to obtain a pouring body;

[0026] S3: when the pouring body is initially cured, scraping and coating a modified mortar on the surface of the pouring body, and obtaining the environmentally-friendly building material regenerated from organic waste after hardening.

[0027] It should be noted that the vibration frequency and amplitude of the vibration compaction in S2 cannot be too large, and the vibration needs to avoid the dissipation of micro-bubbles while eliminating large bubbles.

[0028] In some embodiments, in S1, the mixing mode is stirring at 500-650 rpm for 1-3 min; in S2, the vibration frequency is 40-50 Hz, the vibration amplitude is 0.5-0.6 mm, and the vibration time is 20-30 s.

[0029] In some embodiments, the modified mortar is mixed by quartz sand, VAE emulsion, PVA fiber and water in a mass ratio of 1-2:0.1-0.4:0.01-0.03:1-2; and the scraping and coating thickness of the PVA modified mortar is 40-60% of the thickness of the pouring body.

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] 1. The present application creatively modifies the fibers in the organic waste, greatly enhances the mechanical properties of the fiber composite material by constructing a graphene network coating, and further firmly connects the cellulose and VAE molecular chains through the chemical bonding of silane to form a continuous flexible film layer to coat the fibers, which can effectively inhibit the damage of the cement shrinkage stress to the fibers and avoid the problem of surface fiber shedding, thereby enhancing the mechanical strength and sound insulation performance.

[0032] 2、The cement paste used in the present application significantly optimizes the pore structure distribution of the cement-based material by introducing a bubble structure, and the uniformly distributed closed pores can absorb freeze-thaw stress, and the dynamic synergy of each component in the micro-bubble cement paste forms a bubble dispersion and interface strengthening effect, thereby achieving low-density lightweight of the base material while significantly improving the sound insulation effect of the base material.

[0033] 3、The modified mortar is coated on the surface of the environment-friendly building material, and the modified mortar is filled into the micro-cracks of the mortar to improve the interface density and bonding strength. DETAILED DESCRIPTION

[0034] The present application will be further described in detail below with reference to specific examples.

[0035] Example 1

[0036] An environment-friendly building material regenerated from organic waste, comprising graphene-VAE coated fibers and micro-bubble cement paste in a mass ratio of 1:7.

[0037] The graphene-VAE coated fibers are prepared by the following steps:

[0038] (1) The waste paper and bamboo shoots are cut and soaked and beaten to obtain a fiber slurry;

[0039] (2) The graphene oxide is dispersed in deionized water to obtain a graphene oxide dispersion;

[0040] (3) The fiber slurry is mixed into the graphene dispersion, and ascorbic acid and ferrous chloride are added to reduce the graphene oxide, and the fiber residue is filtered; wherein the mass ratio of organic waste to graphene oxide is 19:1; the amount of reducing agent is 55% of the amount of graphene oxide, and the amount of catalyst is 25% of the amount of graphene oxide;

[0041] (4) The fiber residue is frozen in liquid nitrogen at -196℃ for 10 s, and then dried at -80℃ for 3 h to obtain graphene coated fibers;

[0042] (5) The graphene coated fibers are placed in the VAE emulsion, and KH-550 is added dropwise, and dried to obtain graphene-VAE coated fibers; wherein the amount of silane coupling agent is 2.5% of the amount of organic waste.

[0043] The micro-bubble cement paste comprises the following components by weight fraction: cement 100 parts, nano-silica 7 parts, water reducing agent 0.7 parts, and protein foaming agent 0.3 parts.

[0044] The above micro-bubble cement paste is prepared by the following steps:

[0045] Step 1: Mix silicate cement, nano silica fume, polycarboxylate superplasticizer, and water until there are no clumps to obtain the basic slurry; the amount of water used is 35% of the total amount of cement and nano silica fume.

[0046] Step 2: Mix MCFA foaming agent with water to generate wet foam; wherein, the mass ratio of protein foaming agent to water is 1:40;

[0047] Step 3: Add wet foam to the base slurry to obtain microbubble cement slurry.

[0048] The above-mentioned environmentally friendly building materials made from recycled organic waste are prepared by the following steps:

[0049] S1: Graphene-VAE coated fibers are dispersed into microbubble cement slurry and stirred at 550 rpm for 2 min to obtain fiber-microbubble cement slurry;

[0050] S2: The fiber-microbubble cement slurry is poured and vibrated for 25 seconds at a frequency of 45 Hz and an amplitude of 0.5 mm to obtain the casting body;

[0051] S3: When the cast body is initially set, a modified mortar is scraped onto the surface of the cast body. After hardening, an environmentally friendly building material made from recycled organic waste is obtained. The modified mortar is made by mixing quartz sand, VAE emulsion, PVA fiber and water in a mass ratio of 1:0.2:0.02:1. The thickness of the PVA modified mortar is 40% of the thickness of the cast body.

[0052] Example 2

[0053] It is basically the same as Example 1, except that:

[0054] The environmentally friendly building material provided in this embodiment 2, which utilizes recycled organic waste, includes graphene-VAE coated fibers and microbubble cement slurry in a mass ratio of 1:5.

[0055] The above-mentioned environmentally friendly building materials are prepared by the following steps:

[0056] S1: Graphene-VAE coated fibers are dispersed into microbubble cement slurry and stirred at 500 rpm for 1 min to obtain fiber-microbubble cement slurry;

[0057] S2: The fiber-microbubble cement slurry is poured and vibrated for 20 seconds at a frequency of 40 Hz and an amplitude of 0.5 mm to obtain the casting body;

[0058] S3: when the cast body is initial setting, the modified mortar is scraped on the surface of the cast body, and the environment-friendly building material regenerated by using the organic waste is obtained after hardening; wherein the modified mortar is mixed by quartz sand, VAE emulsion, PVA fiber and water according to the mass ratio of 1:0.1:0.01:1, and the scraping thickness of the PVA modified mortar is 40% of the thickness of the cast body.

[0059] Example 3

[0060] The example 3 is basically the same as example 1, and the difference is only that:

[0061] The environment-friendly building material regenerated by using the organic waste provided by the example 3 comprises graphene-VAE coated fiber and micro-bubble cement paste with a mass ratio of 1:9.

[0062] The above-mentioned environment-friendly building material is prepared by the following steps:

[0063] S1: the graphene-VAE coated fiber is dispersed into the micro-bubble cement paste, and the fiber-micro-bubble cement paste is obtained by stirring at 650 rpm for 3 min;

[0064] S2: the fiber-micro-bubble cement paste is cast, and the cast body is obtained by vibrating at a frequency of 50 Hz and a vibration amplitude of 0.6 mm for 30 s;

[0065] S3: when the cast body is initial setting, the modified mortar is scraped on the surface of the cast body, and the environment-friendly building material regenerated by using the organic waste is obtained after hardening; wherein the modified mortar is mixed by quartz sand, VAE emulsion, PVA fiber and water according to the mass ratio of 1:0.1:0.01:1, and the scraping thickness of the PVA modified mortar is 40% of the thickness of the cast body.

[0066] Example 4

[0067] The example 4 is basically the same as example 1, and the difference is only that:

[0068] The graphene-VAE coated fiber provided by the example 4 is prepared by the following steps:

[0069] (1) the bamboo fiber and the corn cob are cut and soaked and pulped to obtain a fiber pulp;

[0070] (2) the graphene oxide is dispersed in deionized water to obtain a graphene oxide dispersion liquid;

[0071] (3) the fiber pulp is mixed into the graphene dispersion liquid, and L-cysteine and ferric chloride are added to reduce the graphene oxide, and the fiber residue is obtained by filtration; wherein the mass ratio of the organic waste to the graphene oxide is 18:1; the amount of the reducing agent is 50% of the amount of the graphene oxide, and the amount of the catalyst is 20% of the amount of the graphene oxide;

[0072] (4) The fiber residue is frozen in liquid nitrogen at -196℃ for 10 s, and then dried at -80℃ for 2 h to obtain graphene-coated fibers;

[0073] (5) The graphene-coated fibers are placed in a VAE emulsion, and KH-560 is added dropwise, and then dried to obtain graphene-VAE coated fibers; wherein the amount of silane coupling agent is 2% of the amount of organic waste.

[0074] The micro-bubble cement slurry provided in this embodiment 4 comprises the following components by weight fraction: cement 90 parts, nano-silica fume 6 parts, water reducing agent 0.6 parts, and protein foaming agent 0.2 parts.

[0075] The above micro-bubble cement slurry is prepared by the following steps:

[0076] Step one: mix sulphoaluminate cement, nano-silica fume, polycarboxylic acid water reducing agent and water to be cluster-free to obtain a base slurry; wherein the amount of water is 35% of the total amount of cement and nano-silica fume;

[0077] Step two: dilute the MCFA foaming agent with water to generate wet foam; wherein the mass ratio of protein foaming agent to water is 1:38;

[0078] Step three: add the wet foam to the base slurry to obtain a micro-bubble cement slurry.

[0079] Embodiment 5

[0080] The embodiment 5 is basically the same as embodiment 1, except that:

[0081] The graphene-VAE coated fibers provided in this embodiment 5 are prepared by the following steps:

[0082] (1) The waste paper, bamboo shoots, bamboo fibers and corn cobs are cut and soaked and pulped to obtain a fiber pulp;

[0083] (2) The graphene oxide is dispersed in deionized water to obtain a graphene oxide dispersion liquid; and the mixture is uniformly mixed to obtain a graphene reaction liquid;

[0084] (3) The fiber pulp is mixed into the graphene dispersion liquid, ascorbic acid and catalyst ferric ammonium citrate are added to reduce the graphene oxide, and the fiber residue is filtered; wherein the mass ratio of organic waste to graphene oxide is 20:1; the amount of reducing agent is 60% of the amount of graphene oxide, and the amount of catalyst is 30% of the amount of graphene oxide;

[0085] (4) The fiber residue is frozen in liquid nitrogen at -196℃ for 15 s, and then dried at -60℃ for 3 h to obtain graphene-coated fibers;

[0086] (5) Put the graphene-coated fiber into the VAE emulsion, drop KH-570, and dry to obtain graphene-VAE coated fiber; wherein the amount of silane coupling agent is 3% of the amount of organic waste.

[0087] The micro-bubble cement slurry provided by the embodiment 5 comprises the following components in parts by weight: cement 110 parts, nano-silica fume 8 parts, water reducing agent 0.8 parts, and protein foaming agent 0.4 parts.

[0088] The micro-bubble cement slurry is prepared by the following steps:

[0089] Step one: mix sulphoaluminate cement, nano-silica fume, polycarboxylic acid water reducing agent and water to be cluster-free to obtain a base slurry; wherein the amount of water is 40% of the total amount of cement and nano-silica fume;

[0090] Step two: dilute MCFA foaming agent with water to generate wet foam; wherein the mass ratio of protein foaming agent to water is 1:42;

[0091] Step three: add the wet foam to the base slurry to obtain a micro-bubble cement slurry.

[0092] Comparative Example 1

[0093] The embodiment 1 is basically the same, and the only difference is that:

[0094] The preparation steps of graphene-VAE coated fiber omit steps (2), (3) and (4), that is, the fiber is not coated with graphene, but only coated with VAE.

[0095] Comparative Example 2

[0096] The embodiment 1 is basically the same, and the only difference is that:

[0097] The preparation steps of graphene-VAE coated fiber omit step (5), that is, the fiber is not coated with VAE, but only coated with graphene.

[0098] Comparative Example 3

[0099] The embodiment 1 is basically the same, and the only difference is that:

[0100] No micro-bubble cement slurry is added, and is replaced by the same amount of Portland cement.

[0101] In order to prove that the environment-friendly building materials regenerated from organic waste provided by the present application have excellent mechanical properties and light weight, the performance tests of the environment-friendly building materials prepared in Examples 1-5 and Comparative Examples 1-3 are carried out. The determination of dry density is carried out according to the standard GB / T5486-2008, the determination of compressive strength is carried out according to GB / T2542-2012, and the determination of sound insulation improvement amount (thickness 100mm, 125Hz) is carried out according to the standard GB / T 19889.3. The test results are summarized in Table 1.

[0102] Table 1

[0103]

[0104] From Table 1, it can be seen that Examples 1-5 provided by the present application have good mechanical properties, low dry density and excellent sound insulation effect. In combination with the comparative examples, it can be seen that Comparative Example 1 omits graphene coating, Comparative Example 2 omits VAE coating, resulting in a decrease in mechanical strength and sound insulation performance of the environment-friendly building materials, and Comparative Example 3 does not use micro-bubble cement slurry, which greatly reduces the light weight and sound insulation effect of the environment-friendly building materials.

[0105] The above only describes some embodiments of the present application. For those skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application.

Claims

1. An environmentally friendly building material utilizing recycled organic waste, characterized in that, Includes graphene-VAE coated fibers and microbubble cement slurry with a mass ratio of 1:5-9; The graphene-VAE coated fibers are prepared by the following steps: (1) After chopping the organic waste, soak it and pulp it to obtain fiber pulp; (2) Disperse graphene oxide in deionized water to obtain graphene oxide dispersion; (3) The fiber pulp is mixed into the graphene dispersion, and a reducing agent and a catalyst are added to reduce the graphene oxide, and the fiber residue is obtained by filtration. (4) The fiber residue is frozen and then dried to obtain graphene-coated fibers; (5) Place the graphene-coated fiber in VAE emulsion, add silane coupling agent, and dry to obtain the graphene-VAE-coated fiber; The microbubble cement slurry comprises the following components by weight: 90-110 parts cement, 6-8 parts nano silica fume, 0.6-0.8 parts water-reducing agent, and 0.2-0.4 parts protein foaming agent; The microbubble cement slurry is prepared by the following steps: Step 1: Mix the cement, the nano silica fume, the water-reducing agent, and water until there are no clumps to obtain the basic slurry; Step 2: Dilute the protein foaming agent with water to generate wet foam; Step 3: Add the wet foam to the base slurry to obtain the microbubble cement slurry.

2. The environmentally friendly building material utilizing recycled organic waste according to claim 1, characterized in that, The organic waste is selected from at least one of waste paper, bamboo shoot shells, bamboo fiber, and corn cobs; the mass ratio of the organic waste to the graphene oxide is 18-20:

1.

3. The environmentally friendly building material utilizing recycled organic waste according to claim 1, characterized in that, The reducing agent is selected from at least one of ascorbic acid and L-cysteine, and the amount of the reducing agent is 50-60% of the amount of graphene oxide; the catalyst is selected from at least one of ferrous chloride, ferric chloride, and ferric ammonium citrate, and the amount of the catalyst is 20-30% of the amount of graphene oxide.

4. The environmentally friendly building material utilizing recycled organic waste according to claim 1, characterized in that, In step (4), freezing is performed by placing the container in liquid nitrogen at -196°C for 10-15 seconds, drying is performed at -80 to -60°C for 2-3 hours, and the silane coupling agent is selected from at least one of KH-550, KH-560, and KH-570. The amount of silane coupling agent used is 2-3% of the amount of organic waste used.

5. The environmentally friendly building material utilizing recycled organic waste according to claim 1, characterized in that, The cement is selected from at least one of silicate cement and sulfoaluminate cement; in step one, the amount of water used is 35-40% of the total amount of cement and nano silica fume; in step two, the mass ratio of protein foaming agent to water is 1:38-42.

6. A method for preparing environmentally friendly building materials recycled from organic waste as described in any one of claims 1-5, characterized in that, Includes the following steps: S1: Disperse the graphene-VAE coated fibers into the microbubble cement slurry and mix them evenly to obtain fiber-microbubble cement slurry; S2: The fiber-microbubble cement slurry is poured and compacted by vibration to obtain a cast body; S3: When the cast body initially sets, a modified mortar is scraped onto the surface of the cast body. After hardening, the environmentally friendly building material made from recycled organic waste is obtained.

7. The method for preparing environmentally friendly building materials using recycled organic waste according to claim 6, characterized in that, In step S1, the mixing method is stirring at 500-650 rpm for 1-3 min; in step S2, the vibration frequency is 40-50 Hz, the vibration amplitude is 0.5-0.6 mm, and the vibration time is 20-30 s.

8. The method for preparing environmentally friendly building materials using recycled organic waste according to claim 6, characterized in that, The modified mortar is composed of quartz sand, VAE emulsion, PVA fiber and water in a mass ratio of 1-2:0.1-0.4:0.01-0.03:1-2; the thickness of the PVA modified mortar is 40-60% of the thickness of the cast body.

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